“Your products are not generally recognized as safe and effective for the above referenced uses,” the FDA wrote to Texas-based Garden Green Gold, referring to several claims on the company’s website about how CBD could help treat everything from schizophrenia to post-traumatic stress disorder.

“Failure to promptly correct these violations may result in legal action,” the letters warned the companies.

The FDA gave all eight companies 15 days to comply with their warning letters, which are dated Feb. 4 and address a total of 22 products. If the firms don’t stop making medicinal claims, the FDA could seize their property and/or get a court injunction to halt sales.